Process of producing slag-free ferrochromium.



No 1,802, 37, mmrmmm 24 ma.

.T. anupman. I 1PROG'BS'S1OP PRODUCING SLAG FREE FERROGHROMIUMQ v IAPPLICATi'ON FILED JULY 10 1907 UNITED sTA'rns PATENT OFFICE.-

.IOHN ll. IILFrL-xttt); OF FERRISJYVES'I. VIRGINIA, ASSIGNOR TO ELEOTROMETALLURGICAL ("O1\ll..-XNY, OF CHICAGO, ILIAINQIS A CORPORATION OF WESTVIRGINIA.

BBOGESS 0F PnonUorNe- SLAG-FREE FERnocHRoMniM.

Specification oi'Lettera Patent.

Patented March 24, 1908.

Application filed. .n'ii 'io, 901, semi No. 353,059,

To all who-mit mwy concern. Be it known that I, JOHN B. 'HUFFARQ, a'citizen of the United States, residing at Ferris, in the eonnt'y ofFayette and State of West Virginia, have invented certain new and usefulImprovements in lfrooesses of Producing Slag-Free Ferr0ohron1iun1,' ofwhich the following is a specification. I

The slags produced in. the manufacture of ferrochroinium in an electricfurnace are highly basicand infusihle, containing oxids of calcium,.inagne'siuni, chromium. and alu minium insuch proportions that themelting point of the slag isthiglrer than that of the 3" ,In order toeffect a separation of' the slag and. alloy, itiscustomar to tap theentire. contents of the electric furnace into a pot having a refractorylining, allow it to remain therein until the slag and alloy havepartially solidified, and then dump the mass into 'a ter toeornpletcthecooling. Slag'andafih 'herentfused portions of the pot--lining are.

then. broken and chipped away from the alloy by pneumatic hammers orhand tools. This process s expensiveand unsatisfactory as the slag isvery hard and adheres so tenaciously .-that some of it remains and iscarried by the alloy into the molten steel to which the ferrochronii'uinis added, to the injury of. the finished prod net.

The present in ven U051 tin-improved procj ess oi nlitainihg (deanferrool'iroinium by etfectively sgajftthting the molten alloy and slag.Acobrding' to this process the ferro-' chromium and slag are tapped fromthe elec- "tric furnace into a pot-having e. lining.

The heavier alloy'suhsides and the supenneumbent slag quickly s'ohdifiesor stitfens, while the metal beneath remains molten. The tap' hole-1nthe'hottom of the pot is then opened and the molten ferrochromiui'nisrun out into the in ot mold. The solid body of slagis then isehar cdfrom the pot, which is re lined for furt 'ier use.

Suitable apparatus is shown in the aooompanymg drawing, in which thefigure is a transverse vertical section of the pot and 1ngot mold.

The cast iron. pot 1, mounted on Wheels 2, has a tlnn-fire-clay lining3. ,In' the lower end of thepot is a taphole. 4 normally closed by arefractory plug. Beneath the pot is an ingot mold- 5, A body ofsolidified or stiffened slag 6 is shown in the up er half of the pot,while the molten ferroc ironiiuni 7 is flowing through. the open tapholeinto the mold.

I claim:

1. The process of producing metals free. from slags of relatively-highmelting-points, which consists in discharging the molten.

.metal and slag into a vessel, allowing the metal and slag to stratifyand the slag to solidify, and separating the molten metal from the solidslag.

2. The process of producing slag-free ferrochroinium, which consists indischarging the molten ferrochrornium and slag into a vessel,

allowing the alloy and slag to stratify and the SltHl' to solidify, andseparatingthe molten.

alloy from the solid slag.

In testimony whereof, I afhX my signature in presence. of two witnesses.

JOHN B. I-I'UFFARD.

Witnesses:

:1, R. En irANns,

GEO. T. tnizrnas rnn,

